1. Technical Field
Embodiments of the present invention relate to an electrowetting device having a fast response speed and to a method for improving the response speed of an electrowetting device.
2. Description of the Related Art
When a droplet of electrolyte is placed on an electrode and electrical energy is supplied to the electrode-solution interface, a change in interfacial tension occurs, and the contact angle of the droplet is changed. This phenomenon is referred to as electrowetting.
The principle of electrowetting is utilized in various fields, such as liquid lenses, display devices, memory devices, switches, optical devices, liquid magnets, MEMS (micro-electro-mechanical systems), and the like.
Here, a liquid lens is a lens using from a fluid, where the curve of the lens is obtained by the interface between a fluid and an oil. By using the electrowetting phenomenon to modify this interface, it is possible to change the focus of the lens. This technology provides such advantages as a smaller size, a faster response time, and lower power consumption, etc.
Also, a display device using electrowetting may include, from the bottom upwards: a bottom electrode, an insulation layer, a hydrophobic coating, and a pixel wall, where a colored oil may be placed over the hydrophobic coating and water may be added thereto. Such a device may express a pixel by adjusting the area of the oil. That is, light can be made to pass through when a voltage is applied to the oil such that the oil dispersed in each pixel gathers together, and light can be blocked when the applied voltage is removed and the oil blocks the pixel again.
In these various products that utilize electrowetting, a fast response speed is required of the electrowetting device. For example, in order to implement a real-time video clip in an electrowetting display device, a fast response speed is crucial.